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1982 Toyota Corolla 1.8 3 TC Engine; cranks but does not start ( carburated)
All 3 elements for an engine to start are present.
Fuel
spark
compression.
But I couldn't get the car to start. The car is a carburated vehicle. Pounds from an electric fuel pump is 5 psi. I checked for spark again with my test light and spark was jumping to my test light. I took out the spark plugs and they were all wet with fuel and carbon. Cleaned them up and still no fire. If I received spark from my test light, I'm thinking to myself, then there's no need to check the igniter on the vehicle, the igniter is working as it should. What am I missing here?
Two things come to mind. First is, is the spark. How long was the spark from the test point? You may have spark but under compression it might be too weak.
Second is cylinder wash. With fuel soaked plugs just drying is not enough. Squirt a oil cap full of oil into each cylinder.to restore those cylinders. Smell the oil on the dipstick. If fuel smell you'll need to change your oil.
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The following user(s) said Thank You: juergen.scholl
The answer to the first questions is no. The spark wasn't that long to begin with.
I also did not add oil to the cylinder. They might contain more fuel than oil. So I will suggest to customer to change oil.
I want to see the spark line as I'm cranking the engine over. But I'm not sure how to hook up my vantage pro so I can see a waveform. Can you assist? and sorry, I don't do this for a living. Just a shadetree mechanic. thanks
Connect one channel of the vantage to the negative side of the coil and the ground lead to battery negative or a good chassis ground. That way you will capture the primary circuit which will show you burn time, if there is any.
You may want to hook up the second channel to battery positive while cranking, AC-coupled.This will give show you the relative cylinders' compression, just remember that the tdc is indicated by the valley in the trace, not the peak. This second channel will allow you check the spark timing in relation to tdc.
Some other thoughts: Is your fuel ok, no (water) contamination there? What is the story behind, has the car been sitting for a while, did it shut off driving or what ever??
An expert is someone who knows each time more on each time less, until he finally knows absolutely everything about absolutely nothing.
The fuel checks out ok.
The car was running before, as I was told by the owner. It just recently started doing this thing. Cranking but not starting. I will hook up my vantage pro as you suggested and I will get back to you. Thanks for showing me the vantage pro hook up Juergen
Fuel, spark, compression and timing. If the spark isn't happening at the right time, it won't start either.
As far as determining spark strength, I like to use one of those cheap, adjustable gap testers (instead of a light) and set it to around what the gap of the plug should be.
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